It's either a pair of reading glasses, contact lenses, or a monocle (haven't figured out which yet), if you wear it, then the first work of fiction you are subjected to (whether you read it, watch it, play it, etc.) will cause your brain/mind/memories to be erased and overwritten with the mind of a random character from said work of fiction.

If the character in question has superhuman powers, the subject won't get them, but will believe that he/she has them (so if you think you're Superman or something you will be confused as to why you can't fly and will not be afraid of getting shot even though it will still kill you, etc.)

Interesting, but it needs an up of creepy. To many other people, this would look like your excuse to have one of your "FAVORITE COMIC BOOK CHARACTERS!!" to become an SCP. You need something more to fill in the blanks. All I really see being in the description of this SCP are stories about what has happened in testing, which can be nice if well done, but it doesn't really catch a reader's attention. Maybe they could change slightly in appearance (though they don't have the powers), or, even though they don't have the powers of the character, they have the handicaps instead.

Also, a bit more on appearance. Though many SCPs have a general appearance, they usually have some sort of tweak, like strange writing/symbols, being broken, being disproportionate, etc.

Its not the best idea, but I can't see it being taken off the website for being bad. It just needs a little more.

Well the horror is that this essentially kills the person it happens to and replaces them with a deluded mind that's trapped in a world completely different from the one it understands and is then subject to testing and experiments, etc.

It's a standard Magic Item (tm): a random object that has a random, unconnected effect pasted onto it. This could easily be a lamp, a garden hose, an engraved walrus tusk, or a jar of toenail clippings, and it would still be the same item. Take an object from column A and an effect from column B.

This is not how you make a hook, and randomly shoving in horror where it doesn't belong will only worsen things.